Appeal by an employer and its insurance carrier from a decision and award of the Workmen's Compensation Board which found that in exerting "an excessive amount of strength" to dislodge a pick which stuck in the frozen ground in which he was digging, claimant felt chest pain and sustained a coronary thrombosis and myocardial infarction. As grounds for reversal, appellants point to some discrepancy in dates and to some testimony partially contradictory of claimant. Neither seems of great moment but the credibility of the witnesses and the weight of the testimony were, of course, for the board, which was also entirely warranted in accepting the opinion of claimant's attending physician as to causal relationship. Objection to the failure of timely written notice of accident (of which, incidentally, the employer had immediate actual notice) was not properly interposed. (Workmen's Compensation Law, § 18.) Decision and award unanimously affirmed, with costs to the Workmen's Compensation Board.